Recently purchased motorcycle with serial#40ua2534. Does anyone have production numbers for this model. Also interested in originality aspects. This machine has 16" tires,full fenders,chrome lights and bars,saddlebags. Rims,primary,speedo housing all painted. Any assistance would be greatly appreciated. Thanks

You make a good point. Do you know if there were any UA's produced for anything other than sidecar use? Bike appears to be fairly original and complete and that's why I ask. Thanks for production info.

Someone correct me if I'm wrong, but I don't think the UAs came with full skirt fenders and 16" wheels were not an option until 1941?
You might measure the width of the fender straps also and see if they're closer to 1/2" or 7/8".

Sounds like the early narrow brace fenders. According to Palmer's HD military book the UAs were all sidecar equipped as mentioned, but considering the way HDs have been treated over the years it would be no surprise to find the sidecar long gone.

The UA should have skirtless fenders, the taillamp should be the early boattail with lens clips, no screws. The dash cover should be the early one with the pointed chin, carb should be M65.
There's quite a bit to differentiate them, but then you need to start looking at frame casting numbers, transmission date codes, cylinder head markings, etc.
It's very rare for an HD to survive in an original state usually due to perpetual tinkering, especially back when HDs were worth little and half of the stock parts were hauled off to the scrap yard on a regular basis.

Chris is right, UA information is found on pages 123-125 of my military book but UAs were not South African military. South Africa's Union Defense Forces had low compression U models.

UAs, built in 1939 & 1940, were exclusively US Army and were sidecar units. Although sidecar units, they were not equipped with reverse gears. No joke, but there was not enough money to purchase reverse gears at that time. Quantity, to a vehicle starved military, was far more important than whether or not all the bells and whistles could be obtained.

The 1940 UA was equipped with skirtless fenders and had 4.50x18 tires and wheels. There was some chrome (headlamp rim, shift lever, gate, gas caps, and ignition switch but little else). The paint was glossy olive drab (the paint was switched to flat drab and the chrome dropped with the 1941 WLAs).

Also, the only military U models with aluminum heads were the 1939-1940 UAs, all others were iron head U models.

Tried to send some of you guys photos of this bike. If you get them and have any observations, please e-mail me or post on FHP. Also, I'll probably be selling this bike to finance another if anyone is interested. Thanks.

Thanks for chiming in, Bruce. I was a lttle confused before your post, due to the fact your HTRYHD states '39-'40 UA = US Army low comp 74 SV, but someone had stated that UA = South African military? Thanks for setting the record straight.

"They were supplying big twin flatties overseas long after they ceased producing them for the USA."

I seriously doubt the credibility of that statement. Just another old wives tale like Export Knuckles only having a 5 digit serial number. The Big Flatheads were discontinued after the 1948 production. I have never seen, or heard of a 1950 or later Big Twin Flattie overseas or any other place. With the large number of bikes coming home from Europe/Russia some would have shown up by now. The Harleyson's web site in Germany makes no mention of later Big Twin Flatties.

And yet I have had a couple of case sets in my hand stamped 52U. I assisted the owner of Iron and Thunder cycle works in Phoenix AZ in disassembly, inventory, and shelving a large load of parts repatriated from Mexico. This was 1981. The bikes were all bought from a police department warehouse and were seriously used up. The tanks had no emblem strips, all were equipped with 3+R trans and sidecars. The only thing anyone around Phoenix was interested in at the time was the frames, and there wasn't a peach in the pile. None of the bikes were near complete and there were springer and glide parts in the pile, but I don't recall that any of them were bolted together. I wish I had taken pictures or there was someone around to confirm this info, but I can't think of anyone still alive to do so. I moved away at about that time and have no idea where all the junk went. I guess I will just have to be "that nut", that claims to have held legit post domestic production big flat motors in his hands.

A Indonesian guy I know who owns a couple of old bikes told me that some of the local bikes were given different serial numbers. After the war Indonesia got a lot of the Marshall Aid and the army and the police forces used Harleys. Some 15 years ago some 50 or so of these bikes were imported here and I have seen a lot of strange things including odd serial numbers, that do not seem to be restamped.
In some countries the first year in use is important and maybe the Mexican "52U" was stamped in a replacement engine in 1952 for an older chassis and the bike classified as a new motorcycle.
I do not think that 74 U -series motorcycles were produced anywhere after 1948. In theory it is possible that some police force acustomed to use and service flathead-powered sidecar units would be suspicious of the new OHV engines, and replace them with U engines. But it could not be many.
Fiskis

I would love to see those 52U cases. I wouild first look at the date casting code, the line bore numbers and of course the number boss to see if they were legitimate. I have seen all kinds of weird numbers on cases like 1950FLH, 1934EL, 1942EA, all of which were complete phonies.

Even the factory boys stated they U model bikes and engines after 1948 to foreign countries..........no doubt they used up the inventory stock pile they had left from before. I once saw a 50 U that had 47 belly numbers indicating the cases were cast in 1947.
Does anyone else remember when the preservationist/restoration crowd use to state the factory didn't do any custom paint jobs back in the '20s-'30s-'40s? Now they know different!
The moral? Anything is possible when it comes to the older Harley Davidson bikes.